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Income Taxes (Income Tax Expense Differed From Statutory Federal Income Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Statutory federal tax rate	21.00%	21.00%	21.00%
Tax exempt interest income	(0.90%)	(0.70%)	(2.00%)
Tax credits and adjustments	(2.60%)	(2.60%)	(3.40%)
Non-taxable earnings on company owned life insurance	0.00%	(0.60%)	(0.90%)
State taxes, net of federal tax benefit	2.50%	3.00%	1.10%
Nondeductible expenses	0.20%	0.00%	0.10%
Other, net	0.10%	0.00%	0.30%
Effective tax rate	20.30%	20.10%	16.20%

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Effective Income Tax Rate Reconciliation Non Taxable Earnings On Company Owned Life Insurance

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Effective Income Tax Rate Reconciliation, Tax Credit and Adjustments, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes.

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